Diagnostic value of pituitary MRI in differentiation of children with normal growth hormone secretion, isolated growth hormone deficiency and multiple pituitary hormone deficiency.

Pituitary height, volume and morphology were investigated by MRI in patients aged 3.5-24.9 years with growth hormone deficiency (GHD) in relation to birth history and hormonal findings. Three groups with comparable age, sex and pubertal stage were studied: group I (n=42)--patients with isolated growth hormone deficiency (IGHD); group II (n=22)-- patients with multiple pituitary hormone deficiency (MPHD); and group III (n=30)--healthy controls. Pituitary height and volume differed significantly between the three groups, with the smallest in group II and largest in group III (p <0.001 for both). Both variables correlated significantly with peak GH value in the patient groups (p <0.001). The specificity of pituitary dysmorphology in the determination of GHD was 100% and its sensitivity in differentiation of IGHD and MPHD was 95%. Ectopic neurohypophysis was present in 75% of breech births and 27% of head-presenting patients (p <0.01). This study emphasizes the differential diagnostic value of pituitary MRI and its contribution to the understanding of the pathogenesis and prognosis in GHD.